A chamfering cutter is typically required for chamfering the rims of a hole drilled into a workpiece or for chamfering the edges of a workpiece, with a view to removing burrs at the rims or at the edges.
Referring to FIG. 9, a conventional chamfering cutter 5 includes a shaft 51 and a conical cutter head 52. The conical cutter head 52 is provided at one end of the shaft 51 and has at least one cutter groove 521. The cutter groove 521 is so formed that one of its sides forms a cutting edge 522 for cutting the rims of a hole in a workpiece to form chamfered rims or for cutting the edges of the workpiece to form chamfered edges.
Generally, the chamfering cutter 5 is made of high-speed steel (HSS) or other suitable cutter materials, and the cutter groove 521 is formed by grinding. As a result, formation of the cutter groove 521 is slow and costly, which in turn increases the production cost of the chamfering cutter 5. Moreover, if the cutting edge 522 of the chamfering cutter 5 breaks during operation, the entire cutter becomes useless and must be discarded. The conventional chamfering cutters, therefore, are not good for long-term use, and their consumable feature leads to a waste of material and high production cost.
Chamfering cutters with a disposable chamfering blade are also available. The disposable chamfering blade is connected to a cutter body, which usually has a large volume. More specifically, the disposable chamfering blade is provided on one side of the cutter body to form a single eccentric cutting edge. This arrangement, however, tends to give rise to eccentric wobbling or vibration of the blade, so the cutter body must be rotated at low speed. The single-cutting edge design also brings about a low chip removal rate. Consequently, the cutting speed and efficiency of such chamfering cutters are low.